ContentProvider and Database use

Package Practise.lxm.myprovider;import android.net.uri;import android.provider.basecolumns;/** * Created by Administrator on 2015/4/9. * Tool class, provided to call the ContentProvider Contentresolver */public class Words {public    static final String authority = "Lxm.practi Se.provide ";    Word table column name class public    static class Word implements basecolumns{        //Allow operation of column public        static final String _id = "_id"; 
   public static final String word = "word";        public static final String DETAIL = "DETAIL";        The two URI public        static final URI provided by All_words = Uri.parse ("content://" + Authority + "/words");        public static final Uri One_word = Uri.parse ("content://" + Authority + "/word");}    }

Package Practise.lxm.myprovider;import Android.content.contentprovider;import Android.content.contenturis;import Android.content.contentvalues;import Android.content.urimatcher;import Android.database.cursor;import Android.database.sqlite.sqlitedatabase;import android.net.uri;/** * Created by Administrator on 2015/4/9.    */public class MyProvider extends ContentProvider {public static final String table_name= "words";    Operation database Private Mysqliteopendatabase dbhelper;    Urimatcher private static Urimatcher Urimatcher = new Urimatcher (urimatcher.no_match);    Registration code private static final int all_words_code = 1;    private static final int words_id_code = 2;        static {Urimatcher.adduri (words.authority, "Words", All_words_code);    Urimatcher.adduri (words.authority, "word/#", Words_id_code); } @Override public Boolean onCreate () {dbhelper = new Mysqliteopendatabase (This.getcontext (), "myprovider.db3        ", 1);    return true;  }//Query @Override  Public Cursor query (URI uri, string[] projection, string selection, string[] Selectionargs, string sortOrder) {S Qlitedatabase db = Dbhelper.getreadabledatabase (); Get database Operations Object switch (Urimatcher.match (URI)) {//query all case All_words_code:return Db.query (T            Able_name,projection,selection,selectionargs,null,null,sortorder);                Case Words_id_code://Query long id= Contenturis.parseid (URI) by ID;                String Wordswhere = words.word._id + "=" + ID;                if (selection! = null && selection.length () > 0) {wordswhere + = "+" + selection;            } return Db.query (Table_name,projection,wordswhere,selectionargs,null,null,sortorder);        Default://Unknown throw new IllegalArgumentException ("Unknown URI:" + uri.tostring ()); }}//Get type @Override public String getType (URI uri) {switch (Urimatcher.match (URI)) {case A Ll_worDs_code://Multiple return "Vnd.android.cursor.dir/practise.lxm.myprovider.word";            Case Words_id_code://Single return "Vnd.android.cursor.item/practise.lxm.myprovider.word";        Default://Unknown throw new IllegalArgumentException ("Unknown URI:" + uri.tostring ()); }}//New @Override public URI insert (URI uri, contentvalues values) {sqlitedatabase db = DBHELPER.GETW Ritabledatabase ();//Get Operation Database object switch (Urimatcher.match (URI)) {case All_words_code://Add to Number                According to the library long row_id = Db.insert (table_name,null,values);                    if (row_id > 0) {//new success URI Newuri = Contenturis.withappendedid (URI, row_id);                    Notification data has changed GetContext (). Getcontentresolver (). Notifychange (Newuri,null);                return Newuri;            } break; Default://Unknown throw new IllegalArgumentException ("Unknown URI: "+ uri.tostring () +" code: "+ Urimatcher.match (URI));    } return null; } @Override public int delete (URI Uri, String selection, string[] selectionargs) {Sqlitedatabase db = Dbhelp Er.getreadabledatabase ();//Gets the Operation database object int delcount = 0;                Number of deletions switch (Urimatcher.match (URI)) {case Words_id_code://single//Add delete condition, ID for specified value                Long delid = Contenturis.parseid (URI);                String Delwhere = words.word._id + "=" + delid;                if (selection! = null && selection.length () > 0) {delwhere + = "+" + selection;                }//Execute delete delcount = Db.delete (Table_name,delwhere,selectionargs);            Break            Case All_words_code://Delete Multiple Delcount = Db.delete (Table_name,selection,selectionargs);        Default://Unknown throw new IllegalArgumentException ("Unknown URI:" + uri.tostring ());      }  Notification data has changed GetContext (). Getcontentresolver (). Notifychange (Uri,null);    return delcount; } @Override public int update (URI uri, contentvalues values, String selection, string[] selectionargs) {SQLi Tedatabase db = Dbhelper.getwritabledatabase ();//Gets Operation database object int updatecount = 0;                Number of updates switch (Urimatcher.match (URI)) {case Words_id_code://single//Add modify condition, ID is specified value                Long UpdateID = Contenturis.parseid (URI);                String Updatewhere = words.word._id + "=" + UpdateID;                if (selection! = null && selection.length () > 0) {updatewhere + = "+" + selection;                }//Execute delete updatecount = Db.update (table_name,values, Updatewhere,selectionargs);            Break            Case All_words_code://Delete Multiple Updatecount = Db.update (table_name,values, Selection,selectionargs); Default://Unknown throw nEW illegalargumentexception ("Unknown URI:" + uri.tostring ());        }//Notification data changed GetContext (). Getcontentresolver (). Notifychange (Uri,null);    return updatecount; }}

ContentProvider and Database use